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Doppler physics

Alexandre Belli, Pierre Exertier
The paper discusses the issues of radiation exposure that especially occur on the Doppler Orbitography and Radiopositioning Integrated on Satellite (DORIS) Ultra-Stable-Oscillator (USO) that has been placed on Jason-2 oceanography mission as the reference clock. We have studied the frequency response of the Jason-2 USO (launched in June 2008, at 66° of inclination and 1336 km of altitude) over 8.5 years. This is the only mission that provides different sources of data, internal and external, which permit a precise description of the oscillator behavior using several assumptions...
July 11, 2018: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Thomas Apard
The recent development of high-frequency ultrasonography transducers has provided better accuracy and improved the ability to image more superficial body structures. Ultrasonography is a widely available, inexpensive, comparative, and dynamic imaging technique that involves no radiation exposure and has no other adverse effects. Ultrasonography must always be combined with a medical history, physical examination, and radiographic assessment. What is ultrasound-assisted orthopaedic surgery? This approach consists in the use of ultrasonography by orthopaedic surgeons during patient visits and/or in the operating room...
July 7, 2018: Orthopaedics & Traumatology, Surgery & Research: OTSR
Giorgio Margaritondo
A new elementary model of the bending magnet synchrotron radiation is presented, with minimal mathematical formalism. The model explains features not justified by other simplified approaches; in particular, it brings to light the key role of the directional Doppler effect.
July 1, 2018: Journal of Synchrotron Radiation
Bulent Kaya, Saime Paydas, Khairgeldy Aikimbaev, Eda Altun, Mustafa Balal, Ali Deniz, Onur Kaypakli, Mustafa Demirtas
Chronic kidney disease (CKD) patients have a high risk for cardiac arrhythmia. This study aimed to investigate the prevalence of cardiac arrhythmia in CKD patients and to evaluate the relationship between arrhythmia and biochemical and echocardiographic parameters. CKD patients between 18 and 80 years of age were enrolled from the nephrology outpatient clinic. Physical examination, complete blood count, urinalysis biochemical analysis, electrocardiogram, echocardiogram, and 24-h Holter electrocardiogram were performed...
May 2018: Saudi Journal of Kidney Diseases and Transplantation
M Grewal, S Gupta, M Muranjan, S Karande
Deep vein thrombosis and pulmonary thromboembolism are rare and life threatening emergencies in children. We report an 11-year old female who presented with acute complaints of high grade fever, pain in the left thigh and inability to walk and breathlessness since 6 days. On physical examination, there was a diffuse tender swelling of the left thigh, tachypnea, tachycardia with hyperdynamic precordium and bilateral basal crepitations. Ultrasonography and venous doppler of lower limbs showed mild effusion of left hip joint and thrombus in the left common femoral vein and left external iliac vein suggesting a diagnosis of septic arthritis with thrombophlebitis...
June 18, 2018: Journal of Postgraduate Medicine
Nina Paulshus Sundlisæter, Anna-Birgitte Aga, Inge Christoffer Olsen, Hilde Berner Hammer, Till Uhlig, Désirée van der Heijde, Tore K Kvien, Siri Lillegraven, Espen A Haavardsholm
OBJECTIVE: To explore associations between remission, based on clinical and ultrasound definitions, and future good radiographic and physical outcome in early rheumatoid arthritis (RA). METHODS: Newly diagnosed patients with RA followed a treat-to-target strategy incorporating ultrasound information in the Aiming for Remission in rheumatoid arthritis: a randomised trial examining the benefit of ultrasound in a Clinical TIght Control regimen (ARCTIC) trial. We defined 6-month remission according to Disease Activity Score, Disease Activity Score in 28 joints-erythrocyte sedimentation rate, American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) Boolean criteria, Simplified Disease Activity Index, Clinical Disease Activity Index and two ultrasound definitions (no power Doppler signal, grey scale score ≤2)...
June 22, 2018: Annals of the Rheumatic Diseases
Corey R Hart, Gwenael Layec, Joel D Trinity, Yann Le Fur, Jayson R Gifford, Heather L Clifton, Russell S Richardson
Evidence suggests that peak skeletal muscle mitochondrial ATP synthesis rate (Vmax ) in patients with peripheral arterial disease (PAD) may be attenuated due to disease-related impairments in oxygen (O2 ) supply. However, in vitro assessments suggest intrinsic deficits in mitochondrial respiration despite ample O2 availability. To address this conundrum, Doppler ultrasound, near infrared spectroscopy (NIRS), phosphorus magnetic resonance spectroscopy (31 P-MRS), and high-resolution respirometry were combined to assess convective O2 delivery, tissue oxygenation, Vmax , and skeletal muscle mitochondrial capacity (Complex I+II, State 3 respiration), respectively, in the gastrocnemius muscle of 10 patients with early-stage PAD and 11 physical activity-matched healthy controls (HC)...
June 22, 2018: American Journal of Physiology. Heart and Circulatory Physiology
Nicholas R Pettit
CLINICAL INTRODUCTION: A 45-year-old man with no past medical history presents with bilateral lower extremity pain and perineal numbness after walking 10-15 min. The pain starts in his bilateral buttocks and radiates down into his thigh and into his toes. He has no back pain, fever, difficulty urinating or stooling, incontinence or trauma. Social history is positive for smoking. Physical examination was only remarkable for non-dopplerable lower extremity pulses, and he was unable to ambulate down the ED hallway without becoming symptomatic...
July 2018: Emergency Medicine Journal: EMJ
Aleksandra Sljivic, Milena Pavlovic Kleut, Zoran Bukumiric, Vera Celic
INTRODUCTION: Echocardiography represents the most commonly performed noninvasive cardiac imaging test for patients with heart failure (HF). The aim of this study was to assess the relationship between exercise capacity parameters (peak oxygen consumption (VO2) and the minute ventilation-carbon dioxide production relationship (VE/VCO2)), two-dimensional speckle-tracking echocardiography (2D-STE) and three-dimensional echocardiography (3DE) imaging of right ventricular (RV) function in HF patients with reduced ejection fraction (EF)...
2018: PloS One
Foad Abd-Allah, Essam Mahdy Ibrahim, Omar Zidan, Mohamed Abdelhady Mohamed, Amir Abd-Alghafar Mohamdy, Mohammad A Farrag, Alshaimaa M Aboulfotooh, Hisham Abdel-Azim Gomaa
Background: Stroke ranks as the second leading cause of death and the leading cause of morbidity worldwide. Large intracranial arterial stenosis (ICAS) is a major cause of stroke. Methods: This study investigated the prevalence and associated vascular risk factors of ICAS in a high-risk population in Qalyeubia Governorate, Egypt. A cross-sectional pilot survey using transcranial Doppler (TCD) was conducted at Toukh Central Hospital and Aghore El-qubra primary healthcare units in the Qalyeubia Governorate from 1 January 2016 until the end of June 2016...
June 2018: Journal of Vascular and Interventional Neurology
Pairoj Chattranukulchai, Jule Namchaisiri, Monravee Tumkosit, Sarinya Puwanant, Yongkasem Vorasettakarnkij, Suphot Srimahachota, Smonporn Boonyaratavej
BACKGROUND: Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital coronary anomaly. The enlarged right coronary artery provides retrograde collaterals to supply the left ventricle then preferentially directs into the lower pressure pulmonary artery system causing coronary steal phenomenon. Few patients who survive through adulthood without surgery must have abundant, well-formed functioning collaterals with adequate perfusion of the left ventricle...
June 18, 2018: Journal of Cardiothoracic Surgery
Matthias Fluckiger, Tobias Grosshauser, Gerhard Troster
Recent studies suggest that vibration of piano keys affect the perceived quality of the instrument, as well as the dynamic control and timing in piano playing. However, the time signals of piano key vibrations and its physical properties have not been analyzed and compared to the threshold of vibration sensation in a real-life playing situation yet. This study investigates piano key vibrations and explores the diversity of vibrations among different pianos with a laser Doppler vibrometer. A pianist was performing single keystrokes, note sequences, and a music piece excerpt on four concert grand pianos, five grand pianos, and two upright pianos...
April 2018: IEEE Transactions on Haptics
Roshen Borkar, James Rizkalla, Youngmin Kwon, Paul Salama, Maher Rizkalla
Diabetic foot ulcers are systemic diseases that affect all blood vessels within the human body. From major blood vessels to microvasculature, hardening, thickening, and narrowing of blood vessels ultimately results to diminished blood flow to end organs. The detrimental effects of peripheral vascular disease are well recognized across medicine, particularly with regards to diabetic foot ulcers. Diabetic foot ulcers (DFU) are common across all fields of medicine, including but not limited to: orthopedics, vascular surgery, podiatry, general internal medicine, and infectious disease...
June 2018: Journal of Orthopaedics
Agnès Vinet, Philippe Obert, Daniel Courteix, Robert Chapier, Bruno Lesourd, Julien Verney, Frédéric Dutheil, Guillaume Walther
OBJECTIVE: To determine which modality of exercise program (endurance and/or resistance dominance) is the most effective for improving vascular function in the micro- and macrocirculation in metabolic syndrome (MetS). METHODS: Sixty-two MetS patients were enrolled in a 6-month lifestyle intervention program based on diet and exercise training. Each participant was randomly assigned to one of 3 groups categorized by exercise modality (e.g. high-intensity resistance or endurance training, or combined moderate-intensity)...
September 15, 2018: International Journal of Cardiology
Nubyhélia Maria Negreiro de Carvalho, Ana Clemilda Ximenes Marques, Ivon Teixeira de Souza, Vanessa Guerreiro Soares, Felipe Gomes do Nascimento, Letícia Macedo Pinto, Luccas Victor Rodrigues Dias, Guilherme Carneiro Teixeira
Traumatic testis dislocation is an uncommon condition and usually occurs after direct impact on the scrotum. We present an uncommon case of bilateral testicular dislocation caused by an automotive accident, which is the most frequently associated cause described in literature today. Although the fact that diagnosis can be made either by physical examination or with the use of basic exams such as Doppler ultrasound, it is not uncommon for cases to go undetected and diagnosed late. In this case, there was a late diagnosis, almost one year after the motorcycle accident...
2018: Case Reports in Urology
Yanxian Lin, Weiming Song
Objective: To summarize the monitoring methods and preventions of the disorder of blood supplying of expanded flaps, so as to provide some references for improving the survival of expanded flaps. Methods: The domestic and abroad related literature about the disorder of blood supplying of expanded flaps was reviewed and analyzed. Results: Handheld Doppler, digital subtraction angiography, computer tomographic angiography, magnetic resonance angiography, and fluorescein angiography can be used as reliable preoperative imaging methods in designing expanded flaps with rich blood supply...
January 1, 2018: Chinese Journal of Reparative and Reconstructive Surgery
Monzurul Alam, Ghazanfar Ahmed, Yan To Ling, Yong-Ping Zheng
OBJECTIVE: Event-related desynchronization (ERD) is a relative power decrease of electroencephalogram (EEG) signals in a specific frequency band during physical motor execution, while transcranial Doppler (TCD) measures cerebral blood flow velocity. The objective of this study was to investigate the neurovascular coupling in the motor cortex by using an integrated EEG and TCD system, and to find any difference in hemodynamic responses in healthy young male and female adults. APPROACH: Thirty healthy volunteers, aged 20-30 years, were recruited for this study...
June 25, 2018: Physiological Measurement
Antonello D'Andrea, Juri Radmilovic, Stefano Caselli, Andreina Carbone, Raffaella Scarafile, Simona Sperlongano, Giampaolo Tocci, Tiziana Formisano, Francesca Martone, Biagio Liccardo, Michele D'Alto, Eduardo Bossone, Maurizio Galderisi, Paolo Golino
Anabolic-androgenic steroids (AAS) are used by power athletes to improve performance. However, the real effects of the chronic consumption of AAS on cardiovascular structures are subjects of intense debate. To detect by speckle tracking echocardiography (STE) underlying left atrial (LA) dysfunction in athletes abusing AAS and assess possible correlation between LA myocardial function and exercise capacity during cardiopulmonary stress test. 65 top-level competitive bodybuilders were selected (45 males), including 35 athletes misusing AAS for at least 5 years (users), 30 anabolic-free bodybuilders (non-users), compared to 40 age- and sex-matched healthy sedentary controls...
May 22, 2018: International Journal of Cardiovascular Imaging
B Mortimer, A Soler, C R Siviour, F Vollrath
Spiders are fascinating model species to study information-acquisition strategies, with the web acting as an extension of the animal's body. Here, we compare the strategies of two orb-weaving spiders that acquire information through vibrations transmitted and filtered in the web. Whereas Araneus diadematus monitors web vibration directly on the web, Zygiella x-notata uses a signal thread to remotely monitor web vibration from a retreat, which gives added protection. We assess the implications of these two information-acquisition strategies on the quality of vibration information transfer, using laser Doppler vibrometry to measure vibrations of real webs and finite element analysis in computer models of webs...
May 22, 2018: Die Naturwissenschaften
Pardeep K Mittal, Ahmed S Abdalla, Argha Chatterjee, Deborah A Baumgarten, Peter A Harri, Jay Patel, Courtney C Moreno, Helena Gabriel, Frank H Miller
Diagnostic workup of scrotal lesions should begin with a complete clinical history and physical examination, including analysis of risk factors such as family history of testicular cancer, personal history of tumor in the contralateral testis, and cryptorchidism, followed by imaging. Scrotal ultrasonography (US) with a combination of gray-scale and color Doppler techniques has been the first-line imaging modality for evaluation of testicular and extratesticular lesions because of its low cost, wide availability, and high diagnostic accuracy...
May 2018: Radiographics: a Review Publication of the Radiological Society of North America, Inc
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